Although adoption of positive behavior support across one or more state divisions or departments is not yet widespread, implementation in education and community settings and across an individual’s lifespan (referred to as PBS-LS in this chapter) is growing steadily in the United States (Freeman et al., 2021a; Horner et al., 2017; Johnson, 2017). The definition of PBS-LS we use to support children and adults across the lifespan is based on the early definition by Carr and his colleagues (Carr et al., 2002) as well as more recent contributions (Kincaid et al., 2016). PBS-LS is a framework designed on the foundational elements of applied behavior analysis, biomedical research, culturally responsive and person-centered practices, as well as other evidence-based research organized within a systems-change framework (Carr et al., 1999). PBS-LS is a values- and evidence-driven practice used to improve quality of life and thereby naturally reduce and/or prevent behaviors that interfere with a child’s or adult’s ability to grow socially and emotionally and thrive (Carr et al., 2002). Funding for PBS-LS is now used to support children and adults as well as their families and communities across many different services and contexts (Sugai et al., 2009). Funding and implementation of PBS-LS exist across state departments of education, behavioral health, disability services, children and family services/child welfare, juvenile justice, and within services supporting other populations as well (Lucyshyn et al., 2015). Implementation of PBS-LS has helped increase quality of life for people of all age ranges, including birth to three, early childhood, school-age children, youth receiving services transitioning into independent living, and adults and individuals over 65 (Carr et al., 1999; Fisher et al., 2024; Sailor et al., 2009). Examples of PBS-LS exist within alternative settings, including juvenile justice, alternative educational settings, healthcare systems, and psychiatric treatment facilities (Evans et al., 2020; Lucyshyn et al., 2015; Sprague et al., 2013; Sugai et al., 2009).